How do I configure PVST+?

Product and Software: This article applies to all Aruba controllers and ArubaOS 6.0 and later.

 

ArubaOS support of STP:

 

  • Pre-3.4: STP IEEE802.1D
  • 3.4 and later: Rapid Spanning Tree (RSTP) IEEE802.1w
  • 6.0 and later: RSTP and PVST+

PVST+:

 

  • Per VLAN spanning tree plus
  • Cisco proprietary
  • Works on 802.1q links
  • PVST+ maintains a spanning tree instance for each VLAN, which treats each VLAN as a separate network
  • Ability to load balance traffic

How to Configure PVST+

 

1) Configure STP mode to be rapid PVST:

(Aruba3200) (config) #spanning-tree mode ?

rapid Enable Rapid Spanning Tree Protocol (802.1w)

rapid-pvst Per vlan rapid spanning tree mode

(Aruba3200) (config) #spanning-tree mode rapid-pvst

This enables PVST+ globally.

2) Enable STP on the VLANs:

(Aruba3200) (config) #spanning-tree vlan ?

<vlanId> Spanning tree vlan instance

range Range of vlans

(Aruba3200) (config) #spanning-tree vlan 20

(Aruba3200) (config) #spanning-tree vlan range 20-30

This enables STP on the VLANs that want to participate in STP.

 

"Show" Commands Used for Debugging

 

Display in paragraph form the topology change counters:

show spanning-tree

show spanning-tree vlan 20

Display in tabular form the stp state for every port:

show spantree, show spantree vlan 20

Display in tabular form the ports that are forwarding traffic.

show datapath vlan-mcast

 

(Aruba651) #show spanning-tree

 

Spanning Tree instance for vlan 20 -------- STP instance

Spanning Tree is executing the IEEE compatible Rapid Spanning Tree protocol

Bridge Identifier has priority 32768, address 00:0b:86:64:32:70 ------------- Its own bridgeID

Configured hello time 2, max age 20, forward delay 15 --- Timer values

Current root has priority 32768, address 00:0b:86:61:38:10 -------------- Root bridge bridgeID

Topology change flag is set , detected flag not set , changes 4 --------------- Topology change counters

Times: hold 1, topology change 35 hello 2, max age 20, forward delay 15

Timers: hello 1, notification 0

Last topology change: 0 days, 0 hours, 0 mins, 3 secs

Spanning Tree instance for vlan 21

Spanning Tree is executing the IEEE compatible Rapid Spanning Tree protocol

Bridge Identifier has priority 32768, address 00:0b:86:64:32:70

Configured hello time 2, max age 20, forward delay 15

We are the root of the spanning tree

Topology change flag is not set , detected flag not set , changes 0

Times: hold 1, topology change 35 hello 2, max age 20, forward delay 15

Timers: hello 1, notification 0

Last topology change: 6 days, 22 hours, 43 mins, 53 secs

 

(Aruba651) #show spanning-tree vlan 20

 

Spanning Tree instance for vlan 20

Spanning Tree is executing the IEEE compatible Rapid Spanning Tree protocol

Bridge Identifier has priority 32768, address 00:0b:86:64:32:70

Configured hello time 2, max age 20, forward delay 15

We are the root of the spanning tree

Topology change flag is not set , detected flag not set , changes 5

Times: hold 1, topology change 35 hello 2, max age 20, forward delay 15

Timers: hello 1, notification 0

Last topology change: 0 days, 0 hours, 18 mins, 17 secs

 

(Aruba651) # show spantree

 

Spanning tree instance vlan 20 ----------- STP instance

Designated Root MAC 00:0b:86:61:38:10 ----------- Root bridge MAC

Designated Root Priority 32768 ----------- Root bridge priority

Root Cost 4

Root Max Age 20 sec Hello Time 2 sec Forward Delay 15 sec

Bridge MAC 00:0b:86:64:32:70 ----------- Own MAC

Bridge Priority 32768 ------------> Own priority

Configured Max Age 20 sec Hello Time 2 sec Forward Delay 15 sec

Rapid Spanning Tree port configuration

--------------------------------------

Port    State       Cost  Prio  PortFast  P-to-P  Role

----    -----       ----  ----  --------  ------  ----

GE 1/0  Off         4     128   Disable  Enable   Disabled

GE 1/1  Forwarding  4     128   Disable  Enable   Root

GE 1/2  Discarding  4     128   Disable  Enable   Alternate

GE 1/3  Off         100   128   Disable  Enable   Disabled

GE 1/4  Discarding  4     128   Disable  Enable   Disabled

GE 1/5  Discarding  4     128   Disable  Enable   Disabled

GE 1/6  Discarding  4     128   Disable  Enable   Disabled

GE 1/7  Discarding  4     128   Disable  Enable   Disabled

Pc 0    Discarding  100   128   Disable  Enable   Disabled

Pc 1    Discarding  100   128   Disable  Enable   Disabled

Pc 2    Discarding  100   128   Disable  Enable   Disabled

Pc 3    Discarding  100   128   Disable  Enable   Disabled

Pc 4    Discarding  100   128   Disable  Enable   Disabled

Pc 5    Discarding  100   128   Disable  Enable   Disabled

Pc 6    Discarding  100   128   Disable  Enable   Disabled

Pc 7    Discarding  100   128   Disable  Enable   Disabled

Version history
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Last update:
‎07-03-2014 09:47 AM
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